Molecular imaging can help provide a clearer picture of renal health
This powerful tool can help to noninvasively diagnose renal tumors and stratify treatment decision risk.
The expanded use of conventional cross-sectional imaging technologies, including CT scan, ultrasound and MRI, has increased the anatomical detection of renal masses that could indicate cancer or benign lesions that mimic cancer. “But without an invasive procedure such as a biopsy or surgery to remove a tumor or the entire kidney, we can’t differentiate the tiger from the pussycat,” said Mohammad E. Allaf, MD, vice chairman of the Brady Urological Institute and MEA Endowed Professor of Urology and Oncology at the Johns Hopkins University School of Medicine in Baltimore.
Fortunately, the era of molecular imaging for diagnosing renal tumors is here. This advanced imaging technology within the field of nuclear medicine can provide valuable information about the molecular characteristics of renal tumors to inform patients about their condition noninvasively.
“With molecular imaging, we’re no longer operating blind. We can know the molecular underpinnings of tumors for a more precise diagnosis before we make treatment decisions,” Dr. Allaf said.
During the plenary session, “State-of-the-Art Lecture: Advances in Molecular Imaging for Renal Tumors,” on Friday, May 3, at AUA2024 in San Antonio, Dr. Allaf will provide an overview of the latest innovations for the molecular imaging of kidney tumors, including:
- Sestamibi imaging. This common single-photon emission computed tomography molecular imaging test for heart and parathyroid conditions is now being used for renal tumors in clinical practice. “The imaging test can measure mitochondrial abundance,” Dr. Allaf said. A common benign kidney tumor, oncocytoma, is rich in mitochondria; paradoxically, kidney cancer is devoid of it.
- PSMA PET. Prostate-specific membrane antigen positron emission tomography and CT scan or MRI is proving to be a valuable tool for identifying prostate cancer metastases when compared with conventional imaging. “PSMA is overly expressed in prostate cancer and in many different settings, including, as it turns out, the neovasculature of clear cell kidney cancer,” Dr. Allaf said. “We can now take an imaging test marketed for prostate cancer and use it to image kidney cancer. Because this imaging agent may be cleared by the kidney, research is showing that it can be of particular utility to image metastatic sites.”
- Carbonic anhydrase IX imaging. “Carbonic anhydrase IX is a molecule that’s heavily expressed in clear cell kidney cancer,” Dr. Allaf said. The CAIX PET molecular imaging test uses an antibody imaging agent to detect clear cell renal cancer. “Although CAIX imaging isn’t yet Food and Drug Administration approved, we anticipate it will be soon,” he said.
“Molecular imaging will help us noninvasively inform patients of their risk for better decision-making,” Dr. Allaf said. “If patients have a not-so-aggressive tiger or a pussycat and also have compromised kidney function or a bad heart, molecular imaging can help us know there is room to watch and wait. And for patients with tigers, molecular imaging can help us to go into the operating room knowing there was no other solution but surgery.”
